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Osseodensification enhances the stability of endosteal implants. However, pre-clinical studies utilizing osseodensification instrumentation do not account for the limited presence of trabeculae seen clinically. This study aimed to evaluate the effect of osseodensification instrumentation on osteotomy healing in scenarios with and without the presence of trabecular bone. A ~10 cm incision was made over the hip of twelve sheep. Trabecular bone was surgically removed from twelve sites (one site/animal; negative control (Neg. Ctrl)) and left intact at twelve sites (one site/animal; experimental group (Exp.)). All osteotomies were created using the osseodensification drilling protocol. Each osteotomy received an endosteal implant and was evaluated after 3 or 12 weeks of healing (n = 6 animals/time). Histology revealed increased woven and lamellar bone surrounding the implants in the Exp. group relative to the Neg. Ctrl group. The Exp. group demonstrated the presence of bone fragments, which acted as nucleating sites, thereby enhancing the bone formation and remodeling processes. Bone-to-implant contact (%BIC) and bone area fractional occupancy (%BAFO) were significantly higher in the Exp. group relative to the Neg. Ctrl group both at 3 weeks (p = 0.009 and p = 0.043) and 12 weeks (p = 0.010 and p = 0.008). Osseodensification instrumentation in the presence of trabecular bone significantly improved osseointegration. However, no negative influences such as necrosis, inflammation, microfractures, or dehiscence were observed in the absence/limited presence of trabeculae. [ABSTRACT FROM AUTHOR]

Periodontitis is a bacteria‐induced chronic inflammatory disease characterized by degradation of the supporting tissue and bone in the oral cavity. Treatment modalities seek to facilitate periodontal rehabilitation while simultaneously preventing further gingival tissue recession and potentially bone atrophy. The aim of this study was to compare two differently sourced membranes, a resorbable piscine collagen membrane and a porcine‐derived collagen membrane, in the repair of soft tissue defects utilizing a preclinical canine model. This in vivo component consisted of 10 beagles which were subjected to bilateral maxillary canine mucogingival flap defects, as well as bilateral soft tissue defects (or pouches) with no periodontal ligament damage in the mandibular canines. Defects received either a piscine‐derived dermal membrane, (Kerecis® Oral, Ísafjörður, Iceland) or porcine‐derived dermal membrane (Geistlich Mucograft®, Wolhusen, Switzerland) in a randomized fashion (to avoid site bias) and were allowed to heal for 30, 60, or 90 days. Statistical evaluation of tissue thickness was performed using general linear mixed model analysis of variance and least significant difference (LSD) post hoc analyses with fixed factors of time and membrane. Semi‐quantitative analysis employed for inflammation assessment was evaluated using a chi‐squared test along with a heteroscedastic t‐test and values were reported as mean and corresponding 95% confidence intervals. In both the mucogingival flap defects and soft tissue gingival pouches, no appreciable qualitative differences were observed in tissue healing between the membranes. Furthermore, no statistical differences were observed in the thickness measurements between piscine‐ and porcine‐derived membranes in the mucogingival flap defects (1.05 mm [±0.17] and 1.29 mm [±0.17], respectively [p =.06]) or soft tissue pouches (1.36 mm [±0.14] and 1.47 mm [±0.14], respectively [p =.27]), collapsed over time. Independent of membrane source (i.e., piscine or porcine), similar inflammatory responses were observed in both the maxilla and mandible at the three time points (p =.88 and p =.79, respectively). Histologic and histomorphometric evaluation results indicated that both membranes yielded equivalent tissue responses, remodeling dynamics and healing patterns for the mucogingival flap as well as the soft tissue gingival pouch defect models. [ABSTRACT FROM AUTHOR]

Bone regeneration remains a significant clinical challenge, often necessitating surgical approaches when healing bone defects and fracture nonunions. Within this context, the modulation of adenosine signaling pathways has emerged as a promising therapeutic option, encouraging osteoblast activation and tempering osteoclast differentiation. A literature review of the PubMed database with relevant keywords was conducted. The search criteria involved in vitro or in vivo models, with clear methodological descriptions. Only studies that included the use of indirect adenosine agonists, looking at the effects of bone regeneration, were considered relevant according to the eligibility criteria. A total of 29 articles were identified which met the inclusion and exclusion criteria, and they were reviewed to highlight the preclinical translation of adenosine agonists. While preclinical studies demonstrate the therapeutic potential of adenosine signaling in bone regeneration, its clinical application remains unrealized, underscoring the need for further clinical trials. To date, only large, preclinical animal models using indirect adenosine agonists have been successful in stimulating bone regeneration. The adenosine receptors (A1, A2A, A2B, and A3) stimulate various pathways, inducing different cellular responses. Specifically, indirect adenosine agonists act to increase the extracellular concentration of adenosine, subsequently agonizing the respective adenosine receptors. The agonism of each receptor is dependent on its expression on the cell surface, the extracellular concentration of adenosine, and its affinity for adenosine. This comprehensive review analyzed the multitude of indirect agonists currently being studied preclinically for bone regeneration, discussing the mechanisms of each agonist, their cellular responses in vitro, and their effects on bone formation in vivo. [ABSTRACT FROM AUTHOR]

Purpose: To qualitatively and quantitatively evaluate histologic osseointegration parameters of implants designed with decompressing vertical chambers between the threads with two different surface treatments (TiO2 blasting + maleic acid vs TiO2 blasting + maleic + HCl) in a large translational animal model at 3 and 6 weeks in vivo. Materials and Methods: Nine female sheep were used, and 72 implants with trapezoidal threads and decompressing vertical chambers of 0.6 mm in diameter and 0.2 mm in depth were placed in the ilium crest. After 3 and 6 weeks, the animals were euthanized, and biomechanical and histomophometric analyses were performed. Results: Survey histologic evaluation indicated intimate contact between the bone and the implants independent of surface treatment at both times in vivo. Bone formation at both time points depicted an intramembranous-type healing pattern between the implant threads. The mean removal torque values for all groups showed a relative increase in removal torque from 3 to 6 weeks. In terms of bone area fraction occupancy analysis, significant differences were found at 6 weeks between surface treatments (P = .046), where the experimental surface yielded higher degrees of bone area fraction occupancy. Conclusion: Conical implants with decompressing vertical chambers between threads presented similar osseointegration parameters regarding bone-to-implant contact and torque-out test values irrespective of surface treatment. However, shifting from a minimally rough to a moderately rough surface (experimental surface with supplemental acid-etching) resulted in significantly improved bone area fraction occupancy at 6 weeks. [ABSTRACT FROM AUTHOR]

The energy state of endosteal implants is dependent on the material, manufacturing technique, cleaning procedure, sterilization method, and surgical manipulation. An implant surface carrying a positive charge renders hydrophilic properties, thereby facilitating the absorption of vital plasma proteins crucial for osteogenic interactions. Techniques to control the surface charge involve processes like oxidation, chemical and topographical adjustments as well as the application of nonthermal plasma (NTP) treatment. NTP at atmospheric pressure and at room temperature can induce chemical and/or physical reactions that enhance wettability through surface energy changes. NTP has thus been used to modify the oxide layer of endosteal implants that interface with adjacent tissue cells and proteins. Results have indicated that if applied prior to implantation, NTP strengthens the interaction with surrounding hard tissue structures during the critical phases of early healing, thereby promoting rapid bone formation. Also, during this time period, NTP has been found to result in enhanced biomechanical fixation. As such, the application of NTP may serve as a practical and reliable method to improve healing outcomes. This review aims to provide an in-depth exploration of the parameters to be considered in the application of NTP on endosteal implants. In addition, the short- and long-term effects of NTP on osseointegration are addressed, as well as recent advances in the utilization of NTP in the treatment of periodontal disease. [ABSTRACT FROM AUTHOR]

Purpose: The aim of this study was to qualitatively and quantitatively assess the effect of osteotomy preparation by conventional, subtractive, or osseodensification instrumentation on osteotomies, treated with or without endosteal implants, and healing capacity. Materials and Methods: Seven sheep were used, and 56 osteotomies were made in the left and right ilium of the sheep (n = 8/sheep [4 per side/time point (3 and 6 weeks)]). Two different instrumentation techniques were used: (1) conventional/regular drilling in a three-step series of a 2-mm pilot and 3.2-mm and 3.8-mm twist drills and (2) osseodensification drilling with a Densah Bur 2.0-mm pilot and 2.8-mm and 3.8-mm multi-fluted tapered burs. Drilling was performed at 1,100 rpm with saline irrigation. Results: Qualitative histomorphometric evaluation of the osteotomies after 3 and 6 weeks did not indicate any healing impairment due to the instrumentation. In all samples, histologic examination suggested bone remodeling and growth (empty and treated with an implant), irrespective of preparation technique. Osteotomies prepared using the osseodensification instrumentation showed the existence of bone chips autografted into the trabecular spaces along the length of the osteotomy wall. Conclusion: The osseodensification group yielded higher osseointegration rates, as distinguished through qualitative assessment, bone-to-implant contact, and bone-areafraction occupancy, indicating an increased osteogenic potential in osteotomies prepared using the osseodensification technique. [ABSTRACT FROM AUTHOR]

Purpose: The aim of this work was to evaluate osseointegration of endosteal implants with two different surface treatments at early stages (~3 weeks) in the tibia of healthy and ovariectomized rabbits. Materials and Methods: The study comprised 10 adult New Zealand female rabbits (Oryctolagus cuniculus; 6 months and 3.0 ± 0.5 kg). Five animals were subjected to bilateral ovariectomy to mimic osteoporotic-like conditions, and the remaining rabbits (n = 5) served as the healthy control group. After 3 months, specimens from the ovariectomized and control groups were subject to implant placement in both tibiae, using two different types of surface treatment. A total of 36 implants were placed, n = 18 acid-etched and n = 18 anodized. After 3 weeks, euthanasia of the animals was performed, and samples were obtained for processing. Bone-to-implant contact and bone area fraction occupancy were quantified to evaluate the osseointegration parameters around the implant surface and within the thread area, respectively, and nanoindentation tests were performed to determine elastic modulus and hardness of the new bone. Both analyses were performed on the entire implant (total), as well as individually within the cortical and bone marrow cavity area. Results: All animals were evaluated with no signs of infection or postoperative complications. The total bone-to-implant contact and bone area fraction occupancy results, independent of surface treatment, yielded significant differences between the ovariectomized and control groups (P = .002 and P < .001, respectively). In the marrow cavity, analyzing the surface treatments independently as a function of bone condition, the only differences detected were in the anodized treatment (P = .04). Regarding the elastic modulus, differences were detected only with the anodized implants between the ovariectomized and control groups (P = .015). Conclusion: At 3 weeks after implant placement, there were better osseointegration values of the implants in the healthy control group compared with the ovariectomized group independent of surface treatment. Also, specifically in the medullary region of the rabbit tibia, the acid-etched implants had more uniform osseointegration values in conditions of low-quality bone in comparison to the anodized implants, histomorphometrically and biomechanically. [ABSTRACT FROM AUTHOR]

The temporomandibular joint (TMJ) is a complex structure in the cranio-maxillomandibular region. The pathological changes of the joint cause deficiencies at different levels, making its replacement necessary in some cases. The aim of this article is to analyze the current indications, treatment and criteria, and follow-up using a systematic review and case series. A systematic review was carried out, identifying the indications for the use of a customized TMJ prosthesis and evaluating criteria and validation in the international literature. After review and exclusion, 8 articles were included with a minimum follow-up of 12 months. The age of the subjects was between 18 and 47 years old. In 226 patients, 310 TMJ prostheses were installed, 168 bilaterally and 142 unilaterally. In most of the articles, a good condition in the follow-up was observed, with a reduction in pain and better conditions of mandibular movement and function. TMJ prosthesis and replacement is a protocolized, defined, stable, and predictable procedure. Indications and criteria must be evaluated by specialists and patients related to the pathology involved in TMJ deformity or degeneration. Randomized research with an accurate diagnosis and follow-up is necessary to obtain the best indication for this treatment. [ABSTRACT FROM AUTHOR]

The aim of this research was to analyze the facial class, presence of malocclusion, and the mandibular plane and to relate this to the mandibular condyle position. A cross-sectional study in subjects under analysis for orthognathic surgery was done. The mandibular plane, the gonial angle, and the molar class were included to compare the coronal and sagittal position of the condyle and the joint space observed in the CBCT. The measurements were obtained by the same observer at an interval of two weeks. In addition, the Spearman test was performed to determine the correlation using a p value < 0.05 to observe any significant differences. Eighty-nine male and female subjects (18 to 58 years old, 24.6 ± 10.5) were included. In the coronal section, subjects with CIII had a greater mediolateral distance (MLD, p = 0.0001) and greater vertical distance (SID, p = 0.0001) than subjects with CII. In terms of the skeletal class and the mandibular plane, it was observed that subjects in the CII group had a greater mandibular angle (open angle) (p = 0.04) than the CII group and was related to the anterior position of the condyle. The most anterior condylar position was observed in the CII group (p = 0.03), whereas a posterior condylar position was significant in CIII subjects (p = 0.03). We can conclude that the sagittal position of the TMJ was related to the mandibular plane and the skeletal class showing a higher mandibular angle and most anterior position of the condyle in CII subjects and a lower mandibular angle and most posterior position of the condyle in CIII subjects. The implications for surgical treatment have to be considered. [ABSTRACT FROM AUTHOR]

The decisions made during the early stages of a design process have a huge impact on a product. Owing to the explosion of preliminary ideas, however, designers easily lose track of important ideas and significant information and end up being buried in a pile of plain words. Failing to locate an idea in the context of idea generation makes it difficult to generate new ideas or take optimized decisions. In this study, the authors propose the term map approach to provide a complete bird's eye view of all ideas, which is a higher-dimension graphical representation that helps in inspiring ideas and making decisions among design team members. A software application named CoStorm is developed. Through the case study of the cash-flattener module, which is a crucial component of an automated teller machine, this method is found to contribute in facilitating the ideation and decision-making progress. [ABSTRACT FROM AUTHOR]

Background: The maxillary sinus (MS) is described as a pyramid-shaped cavity of the maxilla. Aim: The aim of this research is to present a strategy for morphological analysis of the MS using three-dimensional (3D) printing acquired through cone-beam computed tomography images. Material and Methods: A cross-sectional exploratory, single-blind study was conducted, including 24 subjects. MSs were reconstructed, and 3D virtual modeling was done bilaterally, obtaining 48 physical models generated on a 3D printer. The statistical analysis used tests of normality and tests using a value of P < 0.05 to establish statistical significance. Results: The mean of the MS volume was 15.38 cm3 (±6.83 cm3). The minimum volume was 5.4 cm3 and the maximum was 30.8 cm3. In a bilateral comparison of the right and left volume of the same individual, there were no significant differences (P = 0.353). In relation to the morphology of the MSs, the most prevalent was pyramidal with a square base with a prevalence of 66.7%. Related to gender, significant differences were observed only for the left volume (P = 0.009), with the mean volume being significantly greater in the men (19.69 cm3) than in the women (12.28 cm3). Conclusion: 3D printing of the MS permitted the more precise observation of anatomical features that cannot be seen on a 2D screen. A classification is presented that allows an analysis of sinus morphology, although it is necessary to conduct studies with larger samples to obtain more conclusive results. [ABSTRACT FROM AUTHOR]

The energy analysis of injection moulding processes is influenced by complex interactions amongst the moulded part, its material, the injection machine, the process parameters and the environmental conditions. The availability of energy usage analyses that comprehend information on specific materials and machine kind is limited. This paper reports a study that estimates and analyses the power usage profile (PUP), the specific energy consumption (SEC), and the energy distribution at an operation level of two different injected parts made of acrylonitrile-butadiene-styrene and produced in a hybrid injection moulding machine. The methodology followed by the authors incorporates an experiment carried out in an industrial facility. A large sample size, and data-acquisition and data post-processing processes to obtain an accurate PUP and SEC are used. A breakdown of the energy consumed by the injection moulding process of the parts studied at an operation level using Sankey diagrams is discussed. The study results are used to identify strategies to reduce the energy consumed by the processes. The methodology employed, and the strategies reported could be used with other plastic parts regardless of the material and machine used. The results reported are new experimental data useful input for theoretical models. [ABSTRACT FROM AUTHOR]

Nearly a century ago, the liquid self-balancing device was first introduced by M. LeBlanc for passive balancing of turbine rotors. Although of common use in many types or rotating machines nowadays, little information is available on the unbalance response and stability characteristics of this device. Experimental fluid flow visualization evidences that radial and traverse circulatory waves arise due to the interaction of the fluid backward rotation and the baffle boards within the self-balancer annular cavity. The otherwise destabilizing force induced by trapped fluids in hollow rotors, becomes a stabilizing mechanism when the cavity is equipped with adequate baffle boards. Further experiments using Particle Image Velocimetry (PIV) enable to assess the active fluid mass fraction to be one-third of the total fluid mass. An analytical model is introduced to study the effects of the active fluid mass fraction on a flexible rotor supported by flexible supports excited by bwo different destabilizing mechanisms; rotor internal friction damping and aerodynamic cross-coupling. It is found that the fluid radial and traverse forces contribute to the balancing action and to improve the rotor stability, respectively. [ABSTRACT FROM AUTHOR]

The article presents a case study of a three-year-old boy who was taken to the emergency room for complaints of nausea, vomiting, and generalized seizures. Computed tomography (CT) scan and conventional angiography confirmed the presence of middle cerebral artery (MCA) aneurysm. He underwent microsurgery with tapping and resection of the aneurysm to eliminate mass effect and was discharged in a better condition.

Background: The purpose of the present study was to evaluate the usefulness of the International Association for Trauma Surgery and Intensive Care (IATSIC)/World Health Organization (WHO)'s Guidelines for Essential Trauma Care ( EsTC Guidelines) in providing an internationally applicable and standardized template to assess trauma care capabilities in the South American Region. Methods: Field assessment was conducted in seven provinces (urban and rural, pop. 2,239,509) and 24 facilities (5 large hospitals (LH); 15 small hospitals (SH); 4 basic hospitals (BH)) in Ecuador using EsTC criteria. A total of 260 individual items in Human Resources (HR- availability, clinical knowledge, skills) and physical resources (PR) were evaluated via inspection, review of local statistics, and administrative and staff interviews. EsTC was evaluated on a scale as follows: 0 (absent); 1(inadequate; < 50%); 2 (partly adequate > 50%); 3 (adequate-100%). Results: 210,045 Emergency Department (ED) visits and 61,365 (29%) ED trauma visits were recorded (incidence rate 2,740/100,000 population). Deficits were noted in prehospital trauma care (inadequate coordination, communication), education and training (ATLS < 30%, TNCC 0%), facility based trauma care (poor physical resources [PR] and human resources [HR]), and quality assurance (1/27 hospitals). Conclusions: The IATSIC/WHO EsTC Guidelines provide a simple and useful template to assess trauma care capability in variable facilities and international settings, and they could serve as a valuable tool for trauma system development. Endorsement of EsTC Guidelines by the Panamerican Health Organization and lead trauma societies (the Panamerican Trauma Society) should be considered. [ABSTRACT FROM AUTHOR]

We describe the rare case of a 71-year-old man with a chest mass that was found to be an intrathoracic gossypiboma left 52 years earlier during an emergency lung bilobectomy. This mass was complicated by extension across the chest wall. There are no reports in the literature of a patient carrying a thoracic gossypiboma for such a long period of time, let alone with extension across the chest wall. [ABSTRACT FROM PUBLISHER]

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Platelet-Rich fibrin (PRF) is a three-dimensional (3-D) autogenous biomaterial obtained via simple and rapid centrifugation from the patient’s whole blood samples, without including anti-coagulants, bovine thrombin, additives, or any gelifying agents. At the moment, it is safe to say that in oral and maxillofacial surgery, PRFs (particularly, the pure platelet-rich fibrin or P-PRF and leukocyte and platelet-rich fibrin or L-PRF sub-families) are receiving the most attention, essentially because of their simplicity, cost-effectiveness, and user-friendliness/malleability; they are a fairly new “revolutionary” step in second-generation therapies based on platelet concentration, indeed. Yet, the clinical effectiveness of such surgical adjuvants or regenerative platelet concentrate-based preparations continues to be highly debatable, primarily as a result of preparation protocol variability, limited evidence-based clinical literature, and/or poor understanding of bio-components and clinico-mechanical properties. To provide a practical update on the application of PRFs during oral surgery procedures, this critical review focuses on evidence obtained from human randomized and controlled clinical trials only. The aim is to serve the reader with current information on the clinical potential, limitations, challenges, and prospects of PRFs. Accordingly, reports often associate autologous PRFs with early bone formation and maturation; accelerated soft-tissue healing; and reduced post-surgical edema, pain, and discomfort. An advanced and original tool in regenerative dentistry, PRFs present a strong alternative and presumably cost-effective biomaterial for oro-maxillo-facial tissue (soft and hard) repair and regeneration. Yet, preparation protocols continue to be a source of confusion, thereby requiring revision and standardization. Moreover, to increase the validity, comprehension, and therapeutic potential of the reported findings or observations, a decent analysis of the mechanico-rheological properties, bio-components, and their bioactive function is eagerly needed and awaited; afterwards, the field can progress toward a brand-new era of “super” oro-dental biomaterials and bioscaffolds for use in oral and maxillofacial tissue repair and regeneration, and beyond. [ABSTRACT FROM AUTHOR]